src/operhash.c

   1 /* ircd-ratbox: an advanced Internet Relay Chat Daemon(ircd).
   2  * operhash.c - Hashes nick!user@host{oper}
   3  *
   4  * Copyright (C) 2005 Lee Hardy <lee -at- leeh.co.uk>
   5  * Copyright (C) 2005 ircd-ratbox development team
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions are
   9  * met:
  10  *
  11  * 1.Redistributions of source code must retain the above copyright notice,
  12  *   this list of conditions and the following disclaimer.
  13  * 2.Redistributions in binary form must reproduce the above copyright
  14  *   notice, this list of conditions and the following disclaimer in the
  15  *   documentation and/or other materials provided with the distribution.
  16  * 3.The name of the author may not be used to endorse or promote products
  17  *   derived from this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  21  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  22  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  23  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  24  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  25  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  27  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  28  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  *
  31  */
  32 #include <ratbox_lib.h>
  33 #include "stdinc.h"
  34 #include "match.h"
  35 #include "hash.h"
  36 #include "operhash.h"
  37
  38 #define OPERHASH_MAX_BITS 7
  39 #define OPERHASH_MAX (1<<OPERHASH_MAX_BITS)
  40
  41 #define hash_opername(x) fnv_hash_upper((const unsigned char *)(x), OPERHASH_MAX_BITS)
  42
  43 struct operhash_entry
  44 {
  45         char *name;
  46         int refcount;
  47 };
  48
  49 static rb_dlink_list operhash_table[OPERHASH_MAX];
  50
  51 const char *
  52 operhash_add(const char *name)
  53 {
  54         struct operhash_entry *ohash;
  55         unsigned int hashv;
  56         rb_dlink_node *ptr;
  57
  58         if(EmptyString(name))
  59                 return NULL;
  60
  61         hashv = hash_opername(name);
  62
  63         RB_DLINK_FOREACH(ptr, operhash_table[hashv].head)
  64         {
  65                 ohash = ptr->data;
  66
  67                 if(!irccmp(ohash->name, name))
  68                 {
  69                         ohash->refcount++;
  70                         return ohash->name;
  71                 }
  72         }
  73
  74         ohash = rb_malloc(sizeof(struct operhash_entry));
  75         ohash->refcount = 1;
  76         ohash->name = rb_strdup(name);
  77
  78         rb_dlinkAddAlloc(ohash, &operhash_table[hashv]);
  79
  80         return ohash->name;
  81 }
  82
  83 const char *
  84 operhash_find(const char *name)
  85 {
  86         struct operhash_entry *ohash;
  87         unsigned int hashv;
  88         rb_dlink_node *ptr;
  89
  90         if(EmptyString(name))
  91                 return NULL;
  92
  93         hashv = hash_opername(name);
  94
  95         RB_DLINK_FOREACH(ptr, operhash_table[hashv].head)
  96         {
  97                 ohash = ptr->data;
  98
  99                 if(!irccmp(ohash->name, name))
 100                         return ohash->name;
 101         }
 102
 103         return NULL;
 104 }
 105
 106 void
 107 operhash_delete(const char *name)
 108 {
 109         struct operhash_entry *ohash;
 110         unsigned int hashv;
 111         rb_dlink_node *ptr;
 112
 113         if(EmptyString(name))
 114                 return;
 115
 116         hashv = hash_opername(name);
 117
 118         RB_DLINK_FOREACH(ptr, operhash_table[hashv].head)
 119         {
 120                 ohash = ptr->data;
 121
 122                 if(irccmp(ohash->name, name))
 123                         continue;
 124
 125                 ohash->refcount--;
 126
 127                 if(ohash->refcount == 0)
 128                 {
 129                         rb_free(ohash->name);
 130                         rb_free(ohash);
 131                         rb_dlinkDestroy(ptr, &operhash_table[hashv]);
 132                         return;
 133                 }
 134         }
 135 }